A40

Englund Gambit

9 named lines in this family, ECO A40. Every one of them opens 1. d4 e5, so the notes on those moves are written once, just below, instead of once per line. Under each line you get its moves and the sentences it adds that this page has not already printed. A line's own page carries up to its first 4 per-move notes in full.

The moves every line here plays

1. d4 e5

1. d4 Stakes a claim in the centre, controlling e5, and frees the bishop and queen.
1... e5 Stakes a claim in the centre, controlling d4, and frees the bishop and queen. The pawn is genuinely on offer - this is the Englund Gambit. Fair warning: engines rate this gambit as objectively dubious; it is a practical weapon, not a promise of equality.

Main lineA40

1. d4 e5

In the centre, White holds d4 while Black holds e5.

Hartlaub-Charlick GambitA40

1. d4 e5 2. dxe5 d6

White is up material out of the opening - Black is banking on activity to show for it.

2. dxe5 Takes the pawn on e5, toward the centre and opens the d-file for the queen.
2... d6 Challenges the pawn on e5 - the central tension has to resolve. Theory calls this the Hartlaub-Charlick Gambit.